Why Grading on the Curve Hurts

by Kit Richert, Ph.D.

September 09, 2008

Remember the game of musical chairs? It’s the game where children dance around a circle of chairs to music. When the music stops, kids rush to sit in the chairs. There are never enough chairs for everyone, and the slowest children are out of the game once the faster children have found seats.

The game is set up so that for one person to win, another must lose. A similar game is played in classrooms everyday, from elementary grades to universities… and it’s popular!

Grading on the “Curve” is a method of grading that is based on the belief that letter grades in any given class should be distributed along a bell curve. Typically, an assignment or test is scored, and the average score automatically becomes an average grade (typically a B- or C+). The scores above and below the average are distributed accordingly. For those of us who attended school in the US, we have probably been graded this way at some point.

Traditionally grading on the curve has been viewed as motivational by teachers because it fosters competition. Teachers that curve are both feared and admired for their limited offerings of “As,” and the pressure of being one of the few to get a high grade is believed to stimulate students to work harder, study longer, and take their class more seriously.

Psychology Professor Dr. Marty Covington has spent decades researching the effects of classroom competition on academic motivation at the University of California, Berkeley. His research has lead him to believe that creating competition over a limited number of high grades is more hurtful to motivation than helpful.

Covington’s fundamental belief is that the root of all academic motivation is for students to preserve and enhance a sense of “self-worth.” If students can successfully compete for high grades, they may feel motivated to strive toward that goal, since achieving that will benefit their sense of self-worth. For those who are less likely to compete for top grades, self worth can be preserved successfully by not trying, since failure can be perceived as a lack of effort rather than a lack of intelligence.

In classrooms where rewards are scarce, the inevitable result is that there will be students who try hard but are not rewarded, which threatens self-worth and reduces motivation to work hard. The focus of the exercise becomes the competition, rather than the appreciation of the subject matter itself.

In his book, Making the Grade, A Self-Worth Perspective on Motivation and School Reform Covington writes:

“When conditions of scarcity [of A and B grades] prevail, failure is more likely to be interpreted [by students] as a matter of personal inadequacy, whereas success was often seen as the result of chance or good fortune. … Failure created self-loathing, especially in those students who were high in self-perceived ability. This suggests that under competitive goals, individuals are likely only to continue striving only for as long as they remain successful. No one wants to continue if the result is shame and self-recrimination.”

Of course there are numerous grading alternatives to grading on the curve, but what grading systems can be designed to maximize motivation?

Covington believes that every student should have the opportunity to earn an A. This does not mean that they will, but that they have the opportunity to. In his undergraduate psychology classes at UC Berkeley, Covington tells his students that they can all earn As, and that he wants them to focus on interest and love of learning psychology rather than on earning an A. He attempts to make assignments thought provoking and creative, and gives extra credit assignments to help those students who are not good test takers to demonstrate that they have learned the concepts.

In terms of the curve, it is still widely used at Berkeley. Covington’s mission is to reform grading policies in every academic department on campus. He believes that educating faculty across will help them bring the best out of their students, who at Berkeley tend to be highly anxious about earning As. He hopes that the science of teaching will be improved worldwide such that students will find less pressure and discouragement with grading and instead can be encouraged to focus on the intrinsic rewards that come from learning for learning’s sake.